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The paper deals with the problem of tracking program trajectory for the aircraft in the landing phase. Basic control law, synthesized according to the assumption that required state variables and external disturbances are known, is assumed as a basis for solving the problem of tracking in case of incomplete measurements. As a system of analytical reservation of board instruments, cascade system of...
Satellites are becoming increasingly software dependent. Due to the growth in computer hardware performance and the increasing complexity of space missions, On-Board Software (OBSW) plays nowadays a relevant role in implementing complex system-level requirements. In addition to this, stakeholders need to have preliminary OBSW versions to support satellite integration, testing, and validation activities...
Spacecraft on-board autonomy is an important topic in currently developed and future space missions. In this study, we present a robust approach to the optimal policy of autonomous space systems modeled via Markov Decision Process (MDP) from the values assigned to its transition probability matrix. After addressing the curse of dimensionality in solving the formulated MDP problem via Approximate Dynamic...
In this paper we present the analysis of a measurement technique based on a circular array of three electrostatic sensors, to estimate the trajectory, the charge and the velocity of a moving charged particle, e.g, expelled with the exhaust gases or circulating in the lubricating oil of engines, aero-engines or gas-turbines. In detail, we show how to arrange the information provided by the sensors,...
The interest in maintainability, availability and the techniques to evaluate it had an exponential growth in the last few years, in particular for systems involved in mission-critical environments: these applications demand both high performance and high availability. Maintainability is directly associated to the concept of availability assessment since it concerns failure and recovery aspects of...
In superconducting films, the dissipative flux flow state plays a crucial role in the stability of those devices that operate under bias current whose value is very close to the critical current value, such as superconducting electronics and superconducting single particle/photon detectors. Therefore, we study the voltage stability versus electrical current transport by proper current-voltage measurement...
In the last two decades, the increased production and installation of photovoltaic (PV) plants worldwide has asked for efficient low-cost methods for PV plant inspection to monitor their functionality and guaranteed their performance. To lower maintenance costs new systems have been thought to substitute human workers inspecting the PV plants. The employment of Unmanned Aerial Vehicles (UAVs) has...
In this paper we describe the cylindrical near-field setup developed for the calibration and testing of large size conformai antenna. The antenna under test considered in this work is a not-rotating array used for SSR (Secondary Surveillance Radar) made by elementary radiators disposed along the 360° in the azimuthal plane producing fan-fixed beam along elevation plane. The electronic scanning is...
A benchtop test and certification system for motors and propellers assemblies of small and medium size UAVs (Unmanned Aerial Vehicles) is proposed in this work. In particular, the design and the development of a sensors head and an original embedded test system able to optimally characterize the electrical and the mechanical performances of UAV (voltage supplied to the motor, absorbed current, rotational...
Inertial sensors are increasingly being employed in different types of applications. The reduced cost and the extremely small size makes them the number-one-choice in miniature embedded devices like phones, watches, and small unmanned aerial vehicles. The more complex the application, the more it is necessary to understand the structure of the error signal coming from these sensors. Indeed, their...
Solar ultraviolet (UV) radiation, especially the most energetic UV-C band, is one of the major variables that negatively affects materials performance in space environment. Our work is focused on the design and fabrication of novel nanocomposite films that combine highly conductive graphene nanoplatelets and biological UV-sensitive molecules, which can be used to measure the effects of ultraviolet...
In this work we have performed a sensitivity analysis of the Visual Position Estimator for Rover (VIPER) algorithm using data and images provided by NASA MER exploration rovers and NASA Mars Reconnaissance Orbiter. The algorithm retrieves the rover camera position and orientation relative to a Digital Elevation Model by comparing the skyline extracted from a panoramic image captured by the rover and...
In this paper design, implementation, laboratory and microgravity tests of a space tether length and length rate measurer are discussed. The instrument presented was part of an experimental setup consisting in a new concept of space tether deployer with retrieval capability, which was designed and built in the framework of the Drop Your Thesis! 2016 educational programme, held by the European Space...
We present the preliminary results of a hyperspectral imaging camera in the near medium infrared region (1.5 μm–5 μm) of the electromagnetic spectrum. This region is important to undertake remote sensing by detecting pollutants released by industrial plants, or methane gas leaked by pipes, or even to study the efficiency and the gases produced by combustion reactions. The hyperspectral camera is based...
A procedure to calibrate the relative position and orientation (extrinsic parameters) between a Time of Flight (ToF) camera and an RGB camera is presented. The proposed approach is particularly suited for ToF cameras characterized by very low resolution and a limited field of view. The presented experimental set-up is conceived to facilitate feature detection using both the ToF and RGB cameras. Three...
In this paper, a system for testing light Vertical Take Off and Landing (VTOL) — Remotely Piloted Aircraft System (RPAS), called “DronesBench”, is proposed. This system aims to detect fault related to the RPAS components by measuring the thrust force module, the power consumption and the attitude stability of RPAS under test. In this paper, the system is described and preliminary results are reported...
In order to develop an Automatic Pesticide Detection System an electronic nose based on an array of commercial gas sensors has been realized. The sensors works in parallel and a qualitative response to different pesticides has been found through the use of a self-made measurement bench.
The proposed work aims to realize a highperformances time of flight telemeter, for industrial and aerospace applications. The high-resolution is given by the radiofrequency modulation at about 2 GHz, the high measurement speed is obtained through a real-time embedded elaboration, while the global cost is kept low thanks to commercial telecommunication transceivers and synthesizers. The problems due...
Performance-based Logistics (PBL) contracts require metrics and methodologies set in a systemic way to provide readiness for the warfighter at reasonable costs. There must be a clever and verifiable connection of metrics in order to access and analyze data and to deliver sound and consistent inputs for the entire support system to accomplish its goals. A system of incentives and penalties usually...
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